Kanye went all out to ask for his baby mama's hand, surprising her in front of 50 family members and friends in a private event at San Francisco's AT&T Stadium last night (Oct. 21). The bill for the big romantic gesture? About $6,245,000!

Some $6 million of that reportedly went to the bride-to-be's massive 15-carat ring, but the night's other treats cost a pretty penny as well. The rapper rented out the ballpark for $200,000, projecting his proposal on its Jumbotron. The 50-piece orchestra that accompanied Kanye's bending on one knee can be bought for $5,000 (at the normal rate of $100 per musician per hour).

Additional reported costs include $25,000 for the post-engagement fireworks display and $15,000 for the private jet to take Kimye to the Bay area.

But guests say the expense was worth it. "It was magical," a source tells Us Weekly. "It was the most romantic thing ever -- the ultimate surprise!"